1. Field of the Invention
The present invention relates to an alignment film for liquid crystal, a liquid crystal-sandwiched panel, a liquid crystal display module and a material for liquid crystal alignment film.
2. Description of the Related Art
Heretofore, in liquid crystal display modules for large displays, the STN (supertwisted nematic) system has been adopted to ensure improved visual characteristics. In this STN system, the long axis director of liquid crystal molecules in a cell is twisted 240.degree. to 270.degree.. For the manufacture of liquid crystal display modules in which the STN system is adopted, it is necessary to provide a material for liquid crystal alignment film with which a high pretilt angle is stably attained.
Various methods for obtaining an alignment film for liquid crystal which exhibits a high pretilt angle have been proposed, which include:
(1) a method in which use is made of a polyimide comprising a carbon chain and, bonded thereto, a fluoroalkyl group (see Japanese Patent Application Laid-Open Specification No. 62-174725 and U.S. Pat. No. 4,735,492); PA1 (2) a method in which an amine compound having a long chain fluoroalkyl group is added to a polyimide (see Japanese Patent Application Laid-Open Specification No. 1-180518); and PA1 (3) a method in which a metal complex having a long chain fluoroalkyl group is added to a polyimide (see Preprint for the 13th Liquid Crystal Forum, issued in October, 1987). PA1 ethylene glycol bis(trimellitate anhydride), PA1 1,3-propanediol bis(trimellitate anhydride), PA1 1,4-butanediol bis(trimellitate anhydride), and PA1 1,5-pentanediol bis(trimellitate anhydride). PA1 1,6-hexanediol bis(trimellitate anhydride), PA1 1,7-heptanediol bis(trimellitate anhydride), PA1 1,8-octanediol bis(trimellitate anhydride), PA1 1,9-nonanediol bis(trimellitate anhydride), PA1 1,10-decanediol bis(trimellitate anhydride), PA1 1,12-dodecanediol bis(trimellitate anhydride), and PA1 1,16-hexadecanediol bis(trimellitate anhydride). PA1 butane-1,2,3,4-tetracarboxylic dianhydride, PA1 cyclobutane-1,2,3,4-tetracarboxylic dianhydride, PA1 cyclopentane-1,2,3,4-tetracarboxylic dianhydride, PA1 cyclohexane-1,2,4,5-tetracarboxylic dianhydride, PA1 3,4,3',4'-bicyclohexyltetracarboxylic dianhydride, PA1 bis[bicyclo(2,2,1)hepta-2,3-dicarboxylic anhydride]sulfone, PA1 1,3-di(3,4-dicarboxycyclohexyl)cyclohexanol dianhydride, PA1 bicyclo(2,2,1)hepta-2,3,5,6-tetracarboxylic dianhydride, PA1 bicyclo(2,2,2)octa-7-ene-2,3,5,6-tetracarboxylic dianhydride, PA1 decahydronaphthalene-1,4,5,8-tetracarboxylic dianhydride, and 4,8-dimethyl-1,2,3,5,6,7-hexahydronaphthalene-1,2,5,6-tetracarboxylic dianhydride. These may be used in combination. PA1 pyromellitic anhydride, PA1 3,3',4,4'-diphenyltetracarboxylic dianhydride, PA1 1,2,5,6-naphthalenetetracarboxylic dianhydride, PA1 2,3,6,7-naphthalenetetracarboxylic dianhydride, PA1 2,2', 3,3'-diphenyltetracarboxylic dianhydride, PA1 2,2-bis(3,4-dicarboxyphenyl)propane dianhydride, PA1 bis(3,4-dicarboxyphenyl)sulfone dianhydride, PA1 3,4,9,10-perylenetetracarboxylic dianhydride, PA1 bis(3,4-dicarboxyphenyl) ether dianhydride, PA1 naphthalene-1,2,4,5-tetracarboxylic dianhydride, PA1 naphthalene-1,4,5,8-tetracarboxylic dianhydride, PA1 2,6-dichloronaphthalene-1,4,5,8-tetracarboxylic dianhydride, PA1 2,7-dichloronaphthalene-1,4,5,8-tetracarboxylic dianhydride, PA1 2,3,6,7-tetrachloronaphthalene-1,4,5,8-tetracarboxylic dianhydride, PA1 phenanthrene-1,8,9,10-tetracarboxylic dianhydride, PA1 2,2-bis(2,3-dicarboxyphenyl)propane dianhydride, PA1 1,1-bis(2,3-dicarboxyphenyl)ethane dianhydride, PA1 1,1-bis(3,4-dicarboxyphenyl)ethane dianhydride, PA1 bis(2,3-dicarboxyphenyl)methane dianhydride, PA1 bis(3,4-dicarboxyphenyl)methane dianhydride, PA1 bis(3,4-dicarboxyphenyl)sulfone dianhydride, PA1 benzene-1,2,3,4-tetracarboxylic dianhydride, PA1 3,4,3',4'-benzophenonetetracarboxylic dianhydride, PA1 2,3,2',3'-benzophenonetetracarboxylic dianhydride, PA1 2,3,3',4'-benzophenonetetracarboxylic dianhydride, PA1 pyrazine-2,3,5,6-tetracarboxylic dianhydride, PA1 thiophene-2,3,4,5-tetracarboxylic dianhydride, PA1 ethylenetetracarboxylic dianhydride, PA1 2,3,3',4'-biphenyltetracarboxylic dianhydride, PA1 3,4,3',4'-biphenyltetracarboxylic dianhydride, PA1 2,3,2',3'-biphenyltetracarboxylic dianhydride, PA1 bis(3,4-dicarboxyphenyl)dimethylsilane dianhydride, PA1 bis(3,4-dicarboxyphenyl)methylphenylsilane dianhydride, PA1 bis(3,4-dicarboxyphenyl)diphenylsilane dianhydride, PA1 bis(2,3-dicarboxyphenyl)dimethylsilane dianhydride, PA1 1,4-bis(3,4-dicarboxyphenyldimethylsilyl)benzene dianhydride, PA1 1,3-bis(3,4-dicarboxyphenyl)-1,1,3,3-tetramethyldicyclohexane dianhydride, PA1 p-phenylbis(trimellitic acid monoester anhydride), PA1 4,4'-bis(3,4-dicarboxyphenoxy)diphenyl sulfide dianhydride, PA1 2,2-bis(2,3-dicarboxyphenyl)hexafluoropropane dianhydride, PA1 2,2-bis(3,4-dicarboxyphenyl)hexafluoropropane dianhydride, PA1 2,2-bis[4-(3,4-dicarboxyphenoxy)phenyl]hexafluoropropane dianhydride, PA1 1,4-bis(2-hydroxyhexafluropropyl)benzenebistrimellitic dianhydride, PA1 1,3-bis(2-hydroxyhexafluropropyl)benzenebistrimellitic dianhydride, PA1 (trifluoromethyl)pyromellitic dianhydride, PA1 bis(trifluoromethyl)pyromellitic dianhydride, PA1 5,5'-bis(trifluoromethyl)-3,3',4,4'-biphenyltetracarboxylic dianhydride, PA1 2,2',5,5'-tetrakis(trifluoromethyl)-3,3',4,4'-biphenyltetracarboxylic dianhydride, PA1 5,5'-bis(trifluoromethyl)-3,3',4,4'-diphenyl ethertetracarboxylic dianhydride, PA1 5,5'-bis(trifluoromethyl)-3,3',4,4'-benzophenonetetracarboxylic dianhydride, PA1 bis[(trifluoromethyl)dicarboxyphenoxy]benzene dianhydride, PA1 bis[(trifluoromethyl)dicarboxyphenoxy]biphenyl dianhydride, PA1 bis[(trifluoromethyl)dicarboxyphenoxy](trifluoromethyl)- benzene dianhydride, PA1 bis[(trifluoromethyl)dicarboxyphenoxy]bis(trifluoromethyl)biphenyl dianhydride, PA1 bis[(trifluoromethyl)dicarboxyphenoxy]diphenyl ether dianhydride, PA1 bis(dicarboxyphenoxy)(trifluoromethyl)benzene dianhydride, PA1 bis(dicarboxyphenoxy)bis(trifluoromethyl)benzene dianhydride, PA1 bis(dicarboxyphenoxy)tetrakis(trifluoromethyl)benzene dianhydride, PA1 bis(dicarboxyphenoxy)bis(trifluoromethyl)biphenyl dianhydride, and PA1 bis(dicarboxyphenoxy)tetrakis(trifluoromethyl)biphenyl dianhydride. These may be used in combination. PA1 1,1,1-tris[(phthalic anhydride)-4-yl-carboxymethyl]ethane, PA1 1,1,1-tris[(phthalic anhydride)-4-yl-carboxymethyl]propane, PA1 1,2,3-tris[(phthalic anhydride)-4-yl-carboxy]propane, PA1 1,3,5-tris[(phthalic anhydride)-4-yl-carboxy]hexane, and PA1 1,3,5-tris[(phthalic anhydride)-4-yl-carboxy]benzene. PA1 4-(4-aminophenyl)-3-aminobenzoic acid, PA1 2,2-bis(4-aminophenyl)propane, PA1 2,6-diaminopyridine, PA1 bis(4-aminophenyl)diethylsilane, PA1 bis(4-aminophenyl)diphenylsilane, PA1 bis(4-aminophenyl)ethylphosphine oxide, PA1 bis(4-aminophenyl)-N-butylamine, PA1 bis(4-aminophenyl)-N-methylamine, PA1 N-(3-aminophenyl)-4-aminobenzamide, PA1 3,3'-diaminodiphenylmethane, PA1 3,3'-diaminodiphenyl ether, PA1 3,3'-diaminodiphenyl sulfone, PA1 3,3'-diaminodiphenylpropane, PA1 3,3'-diaminodiphenyl sulfide, PA1 m-xylenediamine, PA1 2,4-diaminotoluene, PA1 2,6-diaminotoluene, PA1 4,4'-diaminodiphenylpropane, PA1 4,4'-diaminodiphenylmethane, PA1 3,3'-diaminobenzophenone, PA1 4,4'-diaminodiphenyl sulfide, PA1 4,4'-diaminodiphenyl sulfone, PA1 4,4'-diaminodiphenyl ether, PA1 3,4'-diaminodiphenyl ether, PA1 1,5-diaminonaphthalene, PA1 2,4-bis(.beta.-amino-t-butyl)toluene, PA1 bis(p-.beta.-amino-t-butyl-phenyl)ether, PA1 bis(p-.beta.-methyl-.gamma.-aminopentyl)benzene, PA1 bis-p-(1,1-dimethyl-5-aminopentyl)benzene, PA1 2,2-bis(4-aminophenyl)hexafluoropropane, PA1 2,2-bis[4-(2-aminophenoxy)phenyl]hexafluoropropane, PA1 2,2-bis[4-(3-aminophenoxy)phenyl]hexafluoropropane, PA1 2,2-bis[4-(4-aminophenoxy)phenyl]hexafluoropropane, PA1 2,2-bis(3-carbamoyl-4-aminophenyl)hexafluoropropane, PA1 2,2-bis[4-(3-carbamoyl-4-aminophenoxy)phenyl]hexafluoropropane, PA1 2,2-bis(3-sulfamoyl-4-aminophenyl)hexafluoropropane, PA1 2,2-bis[4-(3-sulfamoyl-4-aminophenoxy)phenyl]hexafluoropropane, PA1 2,2-bis(3-carboxy-4-aminophenyl)hexafluoropropane, PA1 2,2-bis[4-(3-carboxy-4-aminophenoxy)phenyl]hexafluoropropane, PA1 1,3-bis{2-[4-(4-aminophenoxy)phenyl]hexafluoroisopropyl}benzene, PA1 p-bis(3-carboxy-4-aminophenoxy)tetrafluorobenzene, PA1 4,4'-bis(3-carboxy-4-aminophenoxy)octafluorobiphenyl, PA1 4,4'-diaminooctafluorobiphenyl, PA1 1,2-bis(3-carboxy-4-aminophenyl)tetrafluoroethane, PA1 1,3-bis(3-carboxy-4-aminophenyl)hexafluoropropane, PA1 1,5-bis(3-carboxy-4-aminophenyl)decafluoropentane, PA1 diaminobenzotrifluoride, PA1 bis(trifluoromethyl)phenylenediamine, PA1 diaminotetra(trifluoromethyl)benzene, PA1 diamino(pentafluoroethyl)benzene, PA1 2,2'-bis(trifluoromethyl)benzidine, PA1 2,2'-bis(trifluoromethyl)-4,4'-diaminodiphenyl ether, PA1 bis(aminophenoxy)di(trifluoromethyl)benzene, PA1 bis(aminophenoxy)tetrakis(trifluoromethyl)benzene, PA1 bis[(trifluoromethyl)aminophenoxy]benzene, PA1 bis[(trifluoromethyl)aminophenoxy]biphenyl, PA1 bis{[(trifluoromethyl)aminophenoxy]phenyl}hexafluoropropanehexamethylenedia mine, PA1 heptamethylenediamine, PA1 octamethylenediamine, PA1 nonamethylenediamine, PA1 decamethylenediamine, PA1 tetramethylenediamine, PA1 propylenediamine, PA1 ethylenediamine, PA1 3-methylheptamethylenediamine, PA1 4,4-dimethylheptamethylenediamine, PA1 2,11-diaminododecane, PA1 1,2-bis(3-aminopropoxy)ethane, PA1 2,2-dimethylpropylenediamine, PA1 3-methoxy-hexamethylenediamine, PA1 2,5-dimethylhexamethylenediamine, PA1 2,5-dimethylheptamethylenediamine, PA1 5-methylnonamethylenediamine, PA1 2,17-diaminoeicosadecane, PA1 1,4-diaminocyclohexane, PA1 1,10-diamino-1,10-dimethyldecane, PA1 1,12-diaminooctadecane, PA1 3,3'-dimethyl-4,4'-diaminodiphenylmethane, PA1 3,3'-diethyl-4,4'-diaminodiphenylmethane, PA1 3,3'-dimethoxy-4,4'-diaminodiphenylmethane, PA1 3,3'-diethoxy-4,4'-diaminodiphenylmethane, PA1 3,3'-difluoro-4,4'-diaminodiphenylmethane, PA1 3,3'-dichloro-4,4'-diaminodiphenylmethane, PA1 3,3'-dibromo-4,4'-diaminodiphenylmethane, PA1 3,3'-di(trifluoromethyl)-4,4'-diaminodiphenylmethane, PA1 3,3'-diisopropyl-4,4'-diaminodiphenyl ether, PA1 3,3'-dimethoxy-4,4'-diaminodiphenyl ether, PA1 3,3'-diethoxy-4,4'-diaminodiphenyl ether, PA1 3,3'-difluoro-4,4'-diaminodiphenyl ether, PA1 3,3'-dibromo-4,4'-diaminodiphenyl ether, PA1 3,3'-di(trifluoromethyl)-4,4'-diaminodiphenyl ether, PA1 3,3'-dimethyl-4,4'-diaminodiphenyl sulfone, PA1 3,3'-dimethoxy-4,4'-diaminodiphenyl sulfone, PA1 3,3'-diethoxy-4,4'-diaminodiphenyl sulfone, PA1 3,3'-difluoro-4,4'-diaminodiphenyl sulfone, PA1 3,3'-dichloro-4,4'-diaminodiphenyl sulfone, PA1 3,3'-dibromo-4,4'-diaminodiphenyl sulfone, PA1 3,3'-di(trifluoromethyl)-4,4'-diaminodiphenyl sulfone, PA1 3,3'-dimethyl-4,4'-diaminodiphenylpropane, PA1 3,3'-dimethoxy-4,4'-diaminodiphenylpropane, PA1 3,3'-diethoxy-4,4'-diaminodiphenylpropane, PA1 3,3'-difluoro-4,4'-diaminodiphenylpropane, PA1 3,3'-dichloro-4,4'-diaminodiphenylpropane, PA1 3,3'-dibromo-4,4'-diaminodiphenylpropane, PA1 3,3'-di(trifluoromethyl)-4,4'-diaminodiphenylpropane, PA1 3,3'-dimethyl-4,4'-diaminodiphenyl sulfide, PA1 3,3'-dimethoxy-4,4'-diaminodiphenyl sulfide, PA1 3,3'-diethoxy-4,4'-diaminodiphenyl sulfide, PA1 3,3'-difluoro-4,4'-diaminodiphenyl sulfide, PA1 3,3'-dichloro-4,4'-diaminodiphenyl sulfide, PA1 3,3'-dibromo-4,4'-diaminodiphenyl sulfide, PA1 3,3'-di(trifluoromethyl)-4,4'-diaminodiphenyl sulfide, PA1 3,3'-dimethyl-4,4'-diaminodiphenylhexafluoropropane, PA1 3,3'-dimethoxy-4,4'-diaminodiphenylhexafluoropropane, PA1 3,3'-diethoxy-4,4'-diaminodiphenyihexafluoropropane, PA1 3,3'-difluoro-4,4'-diaminodiphenylhexafluoropropane, PA1 3,3'-dichloro-4,4'-diaminodiphenylhexafluoropropane, PA1 3,3'-dibromo-4,4'-diaminodiphenylhexafluoropropane, PA1 3,3'-di(trifluoromethyl)-4,4'-diaminodiphenylhexafluoropropane, PA1 3,3'-dimethyl-4,4'-diaminobenzophenone, PA1 3,3'-dimethoxy-4,4'-diaminobenzophenone, PA1 3,3'-diethoxy-4,4'-diaminobenzophenone, PA1 3,3'-difluoro-4,4'-diaminobenzophenone, PA1 3,3'-dichloro-4,4'-diaminobenzophenone, PA1 3,3'-dibromo-4,4'-diaminobenzophenone, PA1 3,3'-di(trifluoromethyl)-4,4'-diaminobenzophenone, PA1 3,3'-dimethylbenzidine, PA1 3,3',5,5'-tetramethyl-4,4'-diaminodiphenylmethane, PA1 3,3',5,5'-tetraisopropyl-4,4'-diaminodiphenylmethane, PA1 3,3',5,5'-tetramethoxy-4,4'-diaminodiphenylmethane, PA1 3,3',5,5'-tetraethoxy-4,4'-diaminodiphenylmethane, PA1 3,3',5,5'-tetrafluoro-4,4'-diaminodiphenylmethane, PA1 3,3',5,5'-tetrachloro-4,4'-diaminodiphenylmethane, PA1 3,3',5,5'-tetrabromo-4,4'-diaminodiphenylmethane, PA1 3,3',5,5'-tetra(trifluoromethyl)-4,4'-diaminodiphenylmethane, PA1 3,3',5,5'-tetramethyl-4,4'-diaminodiphenyl ether, PA1 3,3',5,5'-tetraethyl-4,4'-diaminodiphenyl ether, PA1 3,3',5,5'-tetramethoxy-4,4'-diaminodiphenyl ether, PA1 3,3',5,5'-tetraethoxy-4,4'-diaminodiphenyl ether, PA1 3,3',5,5'-tetrafluoro-4,4'-diaminodiphenyl ether, PA1 3,3',5,5'-tetrachloro-4,4'-diaminodiphenyl ether, PA1 3,3',5,5'-tetrabromo-4,4'-diaminodiphenyl ether, PA1 3,3',5,5'-tetra(trifluoromethyl)-4,4'-diaminodiphenyl ether, PA1 3,3',5,5'-tetramethyl-4,4'-diaminodiphenyl sulfone, PA1 3,3',5,5'-tetramethoxy-4,4'-diaminodiphenyl sulfone, PA1 3,3',5,5'-tetraethoxy-4,4'-diaminodiphenyl sulfone, PA1 3,3',5,5'-tetrafluoro-4,4'-diaminodiphenyl sulfone, PA1 3,3',5,5'-tetrachloro-4,4'-diaminodiphenyl sulfone, PA1 3,3',5,5'-tetrabromo-4,4'-diaminodiphenyl sulfone, PA1 3,3',5,5'-tetra(trifluoromethyl)-4,4'-diaminodiphenylsulfone, PA1 3,3',5,5'-tetramethyl-4,4'-diaminodiphenylpropane, PA1 3,3',5,5'-tetramethoxy-4,4'-diaminodiphenylpropane, PA1 3,3',5,5'-tetraethoxy-4,4'-diaminodiphenylpropane, PA1 3,3',5,5'-tetrafluoro-4,4'-diaminodiphenylpropane, PA1 3,3',5,5'-tetrachloro-4,4'-diaminodiphenylpropane, PA1 3,3',5,5'-tetrabromo-4,4'-diaminodiphenylpropane, PA1 3,3',5,5'-tetra(trifluoromethyl)-4,4'-diaminodiphenylpropane, PA1 3,3',5,5'-tetramethyl-4,4'-diaminodiphenyl sulfide, PA1 3,3',5,5'-tetramethoxy-4,4'-diaminodiphenyl sulfide, PA1 3,3',5,5'-tetraethoxy-4,4'-diaminodiphenyl sulfide, PA1 3,3',5,5'-tetrafluoro-4,4'-diaminodiphenyl sulfide, PA1 3,3',5,5'-tetrachloro-4,4'-diaminodiphenylsulfide, PA1 3,3',5,5'-tetrabromo-4,4'-diaminodiphenyl sulfide, PA1 3,3',5,5'-tetra(trifluoromethyl)-4,4'-diaminodiphenyl sulfide, PA1 3,3',5,5'-tetramethyl-4,4'-diaminodiphenylhexafluoropropane, PA1 3,3',5,5'-tetramethoxy-4,4'-diaminodiphenylhexafluoropropane, PA1 3,3',5,5'-tetraethoxy-4,4'-diaminodiphenylhexafluoropropane, PA1 3,3',5,5'-tetrafluoro-4,4'-diaminodiphenylhexafluoropropane, PA1 3,3',5,5'-tetrachloro-4,4'-diaminodiphenylhexafluoropropane, PA1 3,3',5,5'-tetrabromo-4,4'-diaminodiphenylhexafluoropropane, PA1 3,3',5,5'-tetra(trifluoromethyl)-4,4'-diaminodiphenylhexafluoropropane, PA1 3,3',5,5'-tetramethyl-4,4'-diaminobenzophenone, PA1 3,3',5,5'-tetramethoxy-4,4'-diaminobenzophenone, PA1 3,3',5,5'-tetraethoxy-4,4'-diaminobenzophenone, PA1 3,3',5,5'-tetrafluoro-4,4'-diaminobenzophenone, PA1 3,3',5,5'-tetrachloro-4,4'-diaminobenzophenone, PA1 3,3',5,5'-tetrabromo-4,4'-diaminobenzophenone, PA1 3,3',5,5'-tetra(trifluoromethyl)-4,4'-diaminobenzophenone, PA1 3,3',5,5'-tetraisopropyl-4,4'-diaminodiphenylmethane, PA1 3,3'-diisopropyl-5,5'-dimethyl-4,4'-diaminodiphenylmethane, PA1 3,3'-diisopropyl-5,5'-diethyl-4,4'-diaminodiphenylmethane, PA1 3,3'-diisopropyl-5,5'-dimethyl-4,4'-diaminodiphenyl ether, PA1 3,3'-diisopropyl-5,5'-diethyl-4,4'-diaminodiphenyl ether, PA1 3,3'-diisopropyl-5,5'-dimethyl-4,4'-diaminodiphenylpropane, PA1 3,3'-diisopropyl-5,5'-diethyl-4,4'-diaminodiphenylpropane, PA1 3,3'-diisopropyl-5,5'-dimethyl-4,4'-diaminodiphenyl sulfone, PA1 3,3'-diisopropyl-5,5'-diethyl-4,4'-diaminodiphenyl sulfone, PA1 3,3'-bis(trifluoromethyl)benzidine, PA1 2,2'-bis(trifluoromethyl)-4,4'-diaminodiphenyl ether, PA1 3,3'-bis(trifluoromethyl)-4,4'-diaminodiphenyl ether, PA1 3,3',5,5'-tetrakis(trifluoromethyl)-4,4'-diaminodiphenyl ether, PA1 1,3-bis(3-aminopropyl)-1,1,3,3-tetraphenyldisiloxane, PA1 1,3-bis(3-aminopropyl)-1,1,3,3-tetramethyldisiloxane, PA1 1,3-bis(4-aminobutyl)-1,1,3,3-tetramethyldisiloxane.
All of these methods, however, have a drawback in that the pretilt angle obtained is not stable.
Further, in accordance with the increase in the preference for color display modules, a material for liquid crystal alignment film from which a film can be formed at low curing temperatures has increasingly been desired because of the limitation attributed to the heat resistance properties of color filters.